Entangled Telecom Photon Generation using Twisted Van der Waals Crystals
摘要
Nanoscale quantum light sources are essential building blocks for integrated quantum photonic systems. Here, we report a wavelength-scale entangled-photon source based on van der Waals-engineered NbOBr, and benchmark its performance for telecom-wavelength quantum light generation. By exploiting the material's second-order nonlinearity, we generate quantum-correlated photon pairs via spontaneous parametric down-conversion. We then use a 90 twisted stacking to induce quantum interference in photon-pair generation, yielding polarization-entangled photons. This approach enables tunability of the quantum optical state via control of the excitation laser polarization. We experimentally obtain entanglement fidelities exceeding 95% for Bell states, along with a high coincidence-to-accidental ratio of 335, and a brightness approximately one order of magnitude higher than recently reported telecom sources based on transition metal dichalcogenide (TMD) 2D materials. These results establish twisted van der Waals engineering as a powerful platform for highly tunable, high-brightness quantum light sources at telecom wavelengths.
引用
@article{arxiv.2605.14592,
title = {Entangled Telecom Photon Generation using Twisted Van der Waals Crystals},
author = {Nidhin Prasannan and Konstantinos Mourzidis and Vishwas Jindal and Hanting Li and Di Lin and Wenchen Yang and Deng Hu and Liu Yang and Andrea Balocchi and Delphine Lagarde and Pierre Renucci and Zhiwei Wang and Gang Wang and Xavier Marie},
journal= {arXiv preprint arXiv:2605.14592},
year = {2026}
}